Incorrect sizing of scenes iPhone 6 and 6 (iOS Universal)

My app was recently accepted into the Apple Store for iPhones, and it works perfectly fine for the iPhone 4, but not for the 5 or 6, because they have a larger screen size. On those two models, the top and sides of the screen are cut off slightly. I published the version as "iOS Universal", since it is also available for iPads. Is there any way to fix this issue, or will I have to manually submit a version for each screen size (3.5 inches, 4 inches, 4.7 inches and 5.5 inches) ?